JP2012218128A - Gear shaping machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simply-structured gear shaping machine with improved machining accuracy by simplifying gear cutting operations.SOLUTION: The gear shaping machine 1 performs gear cutting on a workpiece W by rotating a cutter 13 and the workpiece W in an engaged state. The machine includes a cutter tilting servo motor 51 for setting an inclination angle θ of the cutter 13, and a cutter-swing servo motor 61 for swinging the cutter 13 between a cutting position and a retreating position. When the cutter 15 set to the inclination angle θ according to a taper shape is positioned at the cutting position and lowered, the workpiece W is tapered by incising the cutter 15 according to the taper shape. When the horizontally held cutter 15 is positioned at the cutting position and lowered, the inclination angle θ is continuously changed according to a crowning shape to crown the workpiece W.

Description

  The present invention relates to a gear shaper capable of performing taper machining and crowning when gears to be machined are cut.

  In general, in a gear shaper, the cutter is reciprocated in the vertical direction while rotating the cutter and the gear to be processed, so that the gear to be processed can be cut. Further, in such a gear shaper, when the gear to be machined is cut, the cutter is tilted at a predetermined inclination angle to enable taper machining and crowning. For example, Patent Document 1 discloses a gear shaper that can perform taper machining and crowning when gears to be machined are cut.

JP 2004-154921 A

  In the conventional gear shaper, the tilting means for tilting the cutter and the releaving means for swinging the cutter between the cut-in position and the retracted position in order to perform taper machining and crowning machining are used as one drive. The motor is also used.

  Thereby, in the conventional gear shaper, a plurality of gears, cams, and rods are combined in a complicated manner in order to interlock the eccentric shaft for tilting the cutter and the cam shaft for swinging the cutter. . In addition, when the mechanical configuration is complicated as described above, the driving force of the driving motor is transmitted along a complicated path, so that the positioning accuracy of the cutter to a predetermined inclination angle, the cutting position and the retracting position of the cutter are as follows. This is a factor that decreases the positioning accuracy. As a result, the conventional gear shaper has a risk of lowering the machining accuracy.

  Accordingly, the present invention solves the above-mentioned problems, and provides a gear shaper capable of improving the machining accuracy by simplifying the configuration and simplifying the gear cutting operation. Objective.

The gear shaper according to the first invention for solving the above-mentioned problems is as follows.
A gear shaper that performs gear cutting on a work gear by rotating the cutter and the work gear in a meshed state with each other,
A spindle on which the cutter is detachably attached to the tip;
The main shaft can be lifted up and down and supported so as to be rotatable around its axis, and the cutter swings so as to approach and separate from the gear to be processed in the cutting direction of the gear to be processed. A cutter head that is supported and movably supported in the cutting direction;
Elevating and moving means for moving the main shaft up and down in the vertical direction;
Tilting means for setting the tilt angle of the cutter by swinging the cutter head;
When the spindle is lowered by the lifting / lowering means, the cutter head is swung to position the cutter at a cutting position for cutting the gear to be machined, while the spindle is raised by the lifting / lowering means. And relieving means for swinging the cutter head and positioning the cutter at a retracted position separated from the gear to be processed,
When the cutter set by the tilting means at the tilt angle corresponding to the taper shape applied to the gear to be processed is positioned at the cutting position by the relieving means, and then the main shaft is lowered by the lifting / lowering means The cutter head is moved in the cutting direction according to the taper shape to taper the gear to be machined, while the cutter held in a horizontal state by the tilting means is moved to the cutting position by the relieving means. After the positioning, the tilt angle of the cutter is continuously changed by the tilting means according to the crowning shape to be applied to the gear to be processed when the spindle is lowered by the lifting / lowering means. And a control means for performing a crowning process.

The gear shaper according to the second invention for solving the above-mentioned problems is
The tilting means is
A first through hole for tilting provided in an outer peripheral portion of the cutter head and opening in a direction perpendicular to the cutting direction;
In the first tilting through-hole, provided with an inclination adjusting shaft inscribed in an eccentric state so as to be rotatable,
The relieving means includes
A swing support member disposed on the same axis as the first tilting through hole and having a second tilting through hole that rotatably supports the tilt adjusting shaft in a biased state;
And a relieving shaft that rotates so as to swing the swing support member in the cutting direction.

A gear shaper according to a third invention for solving the above-described problem is
The control means includes
When the tilting means continuously changes the tilt angle of the cutter according to the crowning shape, the tilting means is controlled in advance according to the position of the tip of the cutter tilted downward. Features.

  Therefore, according to the gear shaper according to the present invention, the configuration is simplified by separately providing the tilting means and the releaving means, and the tilting of the cutter by the tilting means and the swinging of the cutter by the releaving means Since this can be performed independently, simplification of the gear cutting operation can be achieved. Thereby, since the positioning accuracy of the cutter can be improved, the processing accuracy can be improved.

It is a schematic block diagram of the gear shaper which concerns on one Example of this invention. It is a back perspective view of a cutter head. It is AA arrow sectional drawing of FIG. It is the figure explaining the gear cutting operation | movement which performs taper machining in a gear shaper, Comprising: (d) to (a) is the figure which showed the advance operation | movement of a cutter, (a) to (b) is the cutting operation of a cutter. FIGS. 4B to 4C are diagrams illustrating a cutter releaving operation, and FIGS. 3C to 3D are diagrams illustrating a cutter returning operation. It is a figure showing operation of each axis at the time of taper processing. It is a figure explaining gear cutting operation which performs crowning processing in a gear shaper in order, (d) to (a) is a figure showing advance operation of a cutter, (a) to (b) is cutting operation of a cutter FIGS. 4B to 4C are diagrams illustrating a cutter releaving operation, and FIGS. 3C to 3D are diagrams illustrating a cutter returning operation. It is the figure which showed the operation | movement of each axis | shaft at the time of crowning process. It is the figure which showed the inclination state of the cutter at the time of crowning process.

  Hereinafter, the gear shaper according to the present invention will be described in detail with reference to the drawings.

  As shown in FIGS. 1 to 3, the gear shaper 1 supports a column 11 so as to be movable in the horizontal X-axis direction (cutting direction). A saddle 12 is supported on the front surface of the column 11 so as to be movable up and down in the vertical Z-axis direction (feed direction), and a cylindrical cutter head 13 is accommodated in the front portion of the saddle 12.

  A pair of left and right head swing shafts 21 are provided on both sides of the cutter head 13 so as to protrude outward in the radial direction. The head swing shaft 21 is formed on the inner surface of the front portion of the saddle 12. It is rotatably supported. Therefore, the cutter head 13 can swing with respect to the saddle 12 in the X-axis direction around the head swing shaft 21.

  A main shaft 14 is supported in the cutter head 13 so as to be slidable in the axial direction and rotatable about the axis. A cutter 15 is detachably attached to the lower end of the main shaft 14.

  Further, the gear shaper 1 is provided with a rotary table 16 so as to face the cutter head 13 in the X-axis direction. The rotary table 16 is supported so as to be rotatable about its axis, and a work W as a gear to be processed (gear material) is detachably mounted on the upper surface thereof. Although details will be described later, the gear shaper 1 is capable of cutting external teeth and internal teeth with respect to the workpiece W.

  A spindle lifting / lowering servomotor 31 is provided above the cutter head 13, and a screw shaft 32 is connected to the output shaft of the spindle lifting / lowering motor 31. On the other hand, a nut 33 is embedded in the upper end of the main shaft 14, and the nut 33 is engaged with the screw shaft 32. That is, the screw shaft 32 and the nut 33 constitute a ball screw. Therefore, by driving the spindle lifting / lowering servomotor 31, the spindle 14 and the cutter 15 attached thereto can be reciprocated in the axial direction. The spindle lifting / lowering servomotor 31, the screw shaft 32 and the nut 33 constitute lifting / lowering means.

  A spindle rotating servo motor 41 is provided at the front of the cutter head 13, and a drive gear 42 is provided on the output shaft of the spindle rotating servo motor 41. On the other hand, a driven gear 43 is provided on the outer peripheral portion of the main shaft 14, and the driven gear 43 is connected to the drive gear 41 via a plurality of intermediate gears (not shown). Accordingly, by driving the spindle rotating servo motor 41, the spindle 14 and the cutter 15 attached thereto can be rotated around the axis. The main shaft rotating servo motor 41, the driving gear 42, and the driven gear 43 constitute rotating means.

  Further, a pair of left and right tilt support portions 22 are formed on the rear end of the lower end of the cutter head 13 so as to protrude rearward in the X-axis direction. These tilt support portions 22 have through holes (first tilts). Through-holes) 22a are opened. One end side of the swing support member 23 is disposed between the tilt support portions 22, and a through hole (second tilt through hole) 23 a is opened on one end side of the swing support member 23. On the other hand, a through hole (oscillating through hole) 23b is opened on the other end side.

  Here, the through hole 22a and the through hole 23a open in the horizontal direction orthogonal to the X-axis direction and are arranged coaxially. In this way, in the through holes 22a and 23a arranged on the same axis, the inclination adjusting shaft (eccentric shaft) 52 is inscribed in an eccentric state so as to be rotatable, and the inclination adjusting shaft 52 includes a cutter. A tilt servomotor 51 is connected. Therefore, by driving the servo motor 51 for tilting the cutter, the cutter head 13 is swung around the head swinging shaft 21, and the tilt angle of the cutter 15 in the X-axis direction (the radial direction of the workpiece W) with respect to the Z-axis direction. θ (see FIGS. 4, 6, and 8) can be adjusted.

  Specifically, when the inclination adjusting shaft 52 is eccentric right below the through holes 22a and 23a, the rotation angle V (see FIG. 7) of the inclination adjusting shaft 52 is 0 °, and the cutter 15 The inclination angle θ is also 0 °, and the cutter 15 is in a horizontal state. Then, when the inclination adjusting shaft 52 is rotated to one side (right side in the drawing) from the state where the inclination adjusting shaft 52 is eccentric right below the through holes 22a and 23a, the cutter 15 is disposed on the workpiece W side. The cutter tip 15a is tilted so as to face upward. On the other hand, when the inclination adjusting shaft 52 is rotated to the other side (left side in the drawing) from the state in which the inclination adjusting shaft 52 is eccentric right below the through holes 22a and 23a, the cutter 15 is disposed on the workpiece W side. The cutter tip 15a is tilted so as to face downward.

  A cam (not shown) is inscribed in the through hole 23b of the swing support member 23, and a relieving cam shaft 62 is connected to the cam. A cutter swinging servo motor 61 is connected to the relieving cam shaft 62. Accordingly, the cutter head 13 can be swung around the head swing shaft 21 by driving the cutter swing servo motor 61. Thereby, the cutter 15 can be swung in the X-axis direction (the radial direction of the workpiece W) while maintaining the tilted state (tilt angle θ) of the cutter 15.

  The head swing shaft 21, the tilt support portion 22, the cutter tilt servomotor 51, the tilt adjustment shaft 52, etc. constitute tilting means. The head swing shaft 21, the swing support member 23, the cutter swing servo motor 61, the relieving cam shaft 62, and the like constitute relieving means.

  Here, the gear shaper 1 is provided with an NC device (control device) 70 that controls the gear shaper 1 in an integrated manner. The NC device 70 is connected to, for example, the column 11, the saddle 12, the cutter head 13, the spindle lifting servomotor 31, the spindle rotating servomotor 41, the cutter tilting servomotor 51, the cutter swinging servomotor 61, and the like. Yes.

  Therefore, in the NC device 70, based on the gear specifications (taper shape, crowning shape) of the workpiece W set in advance, the processing conditions (the number of cuttings, the cutting position, the cutting amount, the cutting speed, etc.), etc. The tooth cutting operation for external tooth processing and internal tooth processing, that is, the cutting operation, relieving operation, returning operation, forward operation, cutting operation of the cutter 15, and the rotating operation of the cutter 15 and the workpiece W are controlled. ing. As a result, the gear shaper 1 can perform gear cutting on the workpiece W by the cutter 13, and further drives the servo motor 51 for tilting the cutter and the servo motor 61 for swinging the cutter during the above-described gear cutting operation. By controlling the rotation of the tilt adjusting shaft 52 and the relieving cam shaft 62, taper processing and crowning processing can be performed.

  Next, the gear cutting operation of the gear shaper 1 will be described in detail with reference to FIGS.

  When cutting the internal teeth having a tapered shape on the workpiece W, first, the main shaft 14 is rotated, and the rotary table 16 is rotated, so that the cutter 15 and the workpiece W are rotated synchronously. Further, as shown in FIG. 4A, after the inclination adjusting shaft 52 is rotated to one side in accordance with a preset taper shape of the internal teeth, the cutter 15 is positioned at a predetermined inclination angle θ, The relieving cam shaft 61 is rotated to swing the cutter 15 in the X-axis direction. Thereby, the cutter 15 is positioned at a predetermined cutting position.

  Next, as shown in FIG. 4B, the cutter 15 is lowered in the Z-axis direction, and the cutter head 13 is driven according to the taper shape to give the cutter 15 a cut in the X-axis direction. Accordingly, as the cutter 15 descends, the cut of the workpiece W toward the radially outer side is gradually deepened, so that the inner teeth having the tapered shape are formed on a part of the inner peripheral portion of the workpiece W. It is cut (period from time t0 to time t1 in FIG. 5).

  As shown in FIG. 4C, when the cutter 15 is lowered to the lowest position, the relieving cam shaft 62 is rotated to swing the cutter 15 in the X-axis direction. As a result, the cutter 15 is separated (relieved) from the inner peripheral portion of the workpiece W toward the inside in the radial direction, and is positioned at a predetermined retracted position (period from time t1 to time t2 in FIG. 5). .

  Next, as shown in FIG. 4D, the cutter 13 is raised in the Z-axis direction. As a result, the cutter 13 returns to the highest position that is the original height while being separated from the workpiece W (period from time t2 to time t3 in FIG. 5).

  Then, as shown in FIG. 4A, the relieving cam shaft 62 is rotated to swing the cutter 15 in the X-axis direction. Thereby, the cutter 13 moves forward and is positioned at the predetermined cutting position (period from time t3 to time t4 in FIG. 5).

  Next, as shown in FIG. 4B, the cutter 15 is lowered in the Z-axis direction, and the cutter head 13 is driven according to the taper shape to give the cutter 15 a cut in the X-axis direction. Accordingly, as the cutter 15 descends, the cut of the workpiece W toward the radially outer side is gradually deepened, so that a part of the inner peripheral portion of the workpiece W is adjacent to the previously toothed inner teeth. Thus, new internal teeth are continuously cut (period from time t0 to time t1 in FIG. 5).

  Then, by repeating the gear cutting operation as described above, the inner teeth having the tapered shape are cut over the entire circumferential direction of the inner peripheral portion of the workpiece W.

  When cutting the external teeth having a crowning shape on the workpiece W, first, the spindle 14 is rotated and the rotary table 16 is rotated so that the cutter 15 and the workpiece W are rotated synchronously. Further, as shown in FIG. 6A, the tilt adjusting shaft 52 is rotated to hold the cutter 15 in a horizontal state, and the relieving cam shaft 61 is rotated to swing the cutter 15 in the X-axis direction. Move. Thereby, the cutter 15 is positioned at a predetermined cutting position.

  Next, as shown in FIG. 6 (b), the cutter 15 is lowered in the Z-axis direction, and the inclination adjusting shaft 52 is rotated to the other side in accordance with a preset crowning shape of the external teeth. By rotating to one side, the inclination angle θ of the cutter 15 is continuously changed. Thus, as the cutter 15 descends, the cutting of the workpiece W in the radial direction is changed in a curvilinear manner, so that the external teeth having the crowned shape are cut into a part of the outer peripheral portion of the workpiece W. (Period from time t0 to time t1 in FIG. 7).

  Then, as shown in FIG. 6C, when the cutter 15 is lowered to the lowest position, the relieving cam shaft 62 is rotated to swing the cutter 15 in the X-axis direction. Accordingly, the cutter 15 is separated (relieved) from the outer peripheral portion of the workpiece W toward the outer side in the radial direction, and is positioned at a predetermined retracted position (period from time t1 to time t2 in FIG. 7).

  Next, as shown in FIG. 6D, the cutter 13 is raised in the Z-axis direction. As a result, the cutter 13 returns to the highest position that is the original height while being separated from the workpiece W (period from time t2 to time t3 in FIG. 7).

  Then, as shown in FIG. 6A, the relieving cam shaft 62 is rotated to swing the cutter 15 in the X-axis direction. Thereby, the cutter 13 moves forward and is positioned at the predetermined cutting position (period from time t3 to time t4 in FIG. 7).

  Next, as shown in FIG. 6B, the cutter 15 is lowered in the Z-axis direction, and the inclination adjusting shaft 52 is rotated to the other side and then rotated to the one side in accordance with the crowning shape. The inclination angle θ of the cutter 15 is continuously changed. Thereby, as the cutter 15 descends, the cutting in the radial direction of the workpiece W is changed in a curved manner, so that a part of the outer peripheral portion of the workpiece W is adjacent to the outer teeth that have been previously cut, New external teeth are continuously cut (period from time t0 to time t1 in FIG. 7).

  Then, by repeating the gear cutting operation as described above, the external teeth having the crowned shape are cut over the entire circumferential direction of the outer peripheral portion of the workpiece W.

  Here, as shown in FIG. 8, when the cutter 15 is tilted at a predetermined tilt angle θ during crowning, the height position of the tip 15a of the cutter is horizontally increased by the amount of the tilt angle θ. It is arranged below the height position of the cutter tip 15a in the state with a shift amount ΔZ. As described above, when the shift amount ΔZ is generated by tilting the cutter 15, the position of the cutter 15 in the Z-axis direction is controlled using the center position of the lower surface of the cutter 15. However, machining errors in the tooth trace direction and the tooth profile direction are generated with respect to the workpiece W.

  Therefore, in the NC device 70, as shown in FIG. 7, the cutter tilting servomotor 51 is controlled according to the deviation amount ΔZ of the cutter tip 15a based on the crowning shape, and the tilt adjusting shaft 52 is rotated in advance. Let That is, the position of the crowning top of the workpiece W is the central portion in the tooth width direction as understood from the position of the cutter tip 15a in the X-axis direction. The time ta at which the rotation angle V of the inclination adjusting shaft 52 is maximized is set to be earlier than the time tb at which the position of the cutter tip 15a in the X-axis direction is maximized. Thereby, generation | occurrence | production of the processing error of the tooth-tooth direction of a workpiece | work W and a tooth profile direction can be prevented.

  In addition, when the gear shaper 1 is used to simply cut external teeth and internal teeth that do not have a tapered shape or a crowning shape on the workpiece W, the inclination adjusting shaft 52 is rotated to rotate the cutter 15. The above-described gear cutting operation may be performed after positioning in a horizontal state.

  Further, in the above-described embodiment, as the gear cutting operation for tapering the workpiece W, the case of cutting the internal teeth having the taper shape on the workpiece W has been described. The explanation of the case of cutting out the external teeth is omitted because it can be fully understood. Similarly, as the gear cutting operation for performing the crowning process on the workpiece W, the case where the external tooth having the crowning shape is cut on the workpiece W has been described. From this description, the internal tooth having the crowning shape is cut on the workpiece W. The explanation of the case is omitted because it can be fully understood.

  Therefore, according to the gear shaper 1 according to the present invention, the cutter tilting servomotor 51 and the tilt adjusting shaft 52 for tilting the cutter 15, the cutter swinging servomotor 61 for swinging the cutter 15, and By providing the relieving cam shaft 62 separately, the configuration can be simplified. Thereby, the rotation of the tilt adjusting shaft 52 by driving the cutter tilting servomotor 51 and the rotation of the relieving cam shaft 62 by driving the cutter swinging servomotor 61 are independently performed without being involved in each other. Therefore, simplification of the gear cutting operation can be achieved. As a result, it is possible to improve the positioning accuracy of the cutter 15 to the predetermined inclination angle θ and the positioning accuracy of the cutter 15 to the cutting position and the retracted position, so that the processing accuracy can be improved.

  Further, during the gear cutting operation for performing crowning, the inclination adjusting shaft 52 is rotated in advance in accordance with the position of the cutter tip 15a inclined downward in the Z-axis direction, whereby the tooth trace direction and the tooth profile direction of the workpiece W are rotated. Generation of machining errors can be prevented.

  The present invention is applicable to a gear shaper designed to reduce the size and weight of a machine by employing a motor as tilting means.

DESCRIPTION OF SYMBOLS 1 Gear shaper 11 Column 12 Saddle 13 Cutter head 14 Main shaft 15 Cutter 15a Cutter tip 16 Rotary table 21 Head turning shaft 22 Tilt support portion 22a Through hole 23 Swing support members 23a, 23b Through hole 31 Servo motor 32 for raising / lowering the main shaft Screw shaft 33 Nut 41 Spindle rotation servomotor 42 Drive gear 43 Driven gear 51 Cutter tilt servomotor 52 Tilt adjustment shaft 61 Cutter swing servomotor 62 Relieving camshaft 70 NC device W Workpiece

Claims (3)

A gear shaper that performs gear cutting on a work gear by rotating the cutter and the work gear in a meshed state with each other,
A spindle on which the cutter is detachably attached to the tip;
The main shaft can be lifted up and down and supported so as to be rotatable around its axis, and the cutter swings so as to approach and separate from the gear to be processed in the cutting direction of the gear to be processed. A cutter head that is supported and movably supported in the cutting direction;
Elevating and moving means for moving the main shaft up and down in the vertical direction;
Tilting means for setting the tilt angle of the cutter by swinging the cutter head;
When the spindle is lowered by the lifting / lowering means, the cutter head is swung to position the cutter at a cutting position for cutting the gear to be machined, while the spindle is raised by the lifting / lowering means. And relieving means for swinging the cutter head and positioning the cutter at a retracted position separated from the gear to be processed,
When the cutter set by the tilting means at the tilt angle corresponding to the taper shape applied to the gear to be processed is positioned at the cutting position by the relieving means, and then the main shaft is lowered by the lifting / lowering means The cutter head is moved in the cutting direction according to the taper shape to taper the gear to be machined, while the cutter held in a horizontal state by the tilting means is moved to the cutting position by the relieving means. After the positioning, the tilt angle of the cutter is continuously changed by the tilting means according to the crowning shape to be applied to the gear to be processed when the spindle is lowered by the lifting / lowering means. A gear shaper comprising: control means for performing crowning. The gear shaper according to claim 1,
The tilting means is
A first through hole for tilting provided in an outer peripheral portion of the cutter head and opening in a direction perpendicular to the cutting direction;
In the first tilting through-hole, provided with an inclination adjusting shaft inscribed in an eccentric state so as to be rotatable,
The relieving means includes
A swing support member disposed on the same axis as the first tilting through hole and having a second tilting through hole that rotatably supports the tilt adjusting shaft in a biased state;
A gear shaper comprising: a relieving shaft that rotates to swing the swing support member in a cutting direction. In the gear shaper according to claim 1 or 2,
The control means includes
When the tilting means continuously changes the tilt angle of the cutter according to the crowning shape, the tilting means is controlled in advance according to the position of the tip of the cutter tilted downward. Features gear shaper.

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